bt-device: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/bt-device - from package: bluez-tools

You may install the required package with command apt-get install {package}

Error in other languages:
bt-device: bevel nie gevind nie
bt-device: comandă negăsită
bt-device: comando não encontrado
bt-device: commande introuvable
bt-device: command not found
bt-device: käsku ei ole
bt-device: không tìm thấy lệnh
bt-device: komanda nerasta
bt-device: Kommando nicht gefunden.
bt-device: kommandot finns inte
bt-device: komut yok
bt-device: nie znaleziono polecenia
bt-device: níor aimsíodh an t-ordú
bt-device: no se encontró la orden
bt-device: no s'ha trobat l'ordre
bt-device: opdracht niet gevonden
bt-device: parancs nem található
bt-device: perintah tidak ditemukan
bt-device: príkaz nenájdený
bt-device: příkaz nenalezen
bt-device: команда не найдена
bt-device: командата не е открита
bt-device: 命令找不到
bt-device: コマンドが見つかりません